Patho: Skin Cancer

ABCDEs of Skin Cancer

Asymmetry One half of a mole does not match the other. Border The edges are irregular, ragged, notched or blurred. Color The mole is not evenly colored. It may include shades of brown or black, or patches of red or pink. Diameter The spot is larger than 6 millimeters across. Evolving The mole is changing in size, shape, or color.

characteristics of melanoma

Asymmetry, irregular borders, multiple colors, and a diameter greater than 6 millimeters.

greatest risk factors for skin cancers.

Ultraviolet (UV) exposure, including sunlight or artificial tanning.

Skin Cancer Risk Factors

Ultraviolet Exposure: Having one or more blistering sunburns, especially as a child, can significantly increase the risk Skin Type: lighter the skin tone. Having many moles Family or Personal Skin Cancer History Age and Geographic Location: Increasing age increases the risk and lives in an area of higher elevation or closer to the equator, when sunlight exposure is stronger Medication or Toxic Exposure to Certain Substances: receiving chemotherapy or radiation. Conditions requiring biologic response modifiers (BRMs) and disease-modifying antirheumatic drugs (DMARDs). Exposure to certain chemicals, such as arsenic, and certain types of radiation. infliximab (an immunosuppressive) Genetics and Immune System Suppression genetic conditions such as xeroderma pigmentosum or nevoid basal cell carcinoma syndrome Exposure to certain chemicals, such as arsenic, and certain types of radiation

Melanoma

arises from melanocytes that have mutated and grown atypically. aggressive and may rapidly spread to other parts of the body if not treated early. Certain genetic factors and mutations in genes, including BRAF and NRAS, play a crucial role in melanoma development.​

Nonmelanoma skin cancers include

basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and several rare cancers. often activated by ultraviolet exposure.

nevus

benign growth formed by a cluster of melanocytes, expressing melanin, which appears darker than the surrounding skin.

used to diagnose skin cancer

biopsy of the suspected lesion

Dermatoscopy

can be used to evaluate moles for irregularities suggestive of skin cancer.

Melanoma Clinical Manifestations

develop in an existing mole that changes size, shape, or color or as a new, unusual-looking growth on your skin. Melanoma is more aggressive than BCC and SCC. It can spread quickly to other parts of the body and is the deadliest form of skin cancer if not detected early. It grows mostly downward and can eventually spread to organs. The most common place it spreads (metastasizes) is to the brain.

A skin assessment for skin cancer should include

examination of moles in all skin areas, including the bottom of the foot, between the toes, and under the fingernails, as any mole may become a melanoma.

Squamous cell carcinoma (SCC) Clinical Manifestations

firm, red nodule or a flat lesion with a scaly, crusted surface. It is mostly found on sun-exposed areas such as the face, ears, neck, arms, and chest. SCC can grow more rapidly than BCC and has a greater risk of spreading to other parts of the body, especially if it is not treated early.

Moles (nevi)

made up of pigment-producing cells in the skin called melanocytes multiply due to various factors, including ultraviolet radiation exposure, hormonal changes, and genetic factors They grow and cluster between the epidermis and the epidermal-dermal junction. This cluster creates a nevus on the skin surface. A nevus reaches a mature state and remains stable. Once mature, it does not typically grow or change color. If there is a change after maturation, mutation is suspected. If the mutation grows, the risk of skin cancer increases. *Moles are made up of skin cells called melanocytes. These cells are triggered to multiply due to various factors, including sun exposure and hormonal changes. ​ Cells grow and cluster in the epidermis. After maturation, mutations in these moles can lead to skin cancer.

Melanocytes produce

melanin, skin pigment color.

Skin cancer is divided into two general categories:

nonmelanoma and melanoma.

Basal cell carcinoma (BCC) Clinical Manifestations

pearly or waxy bump on sun-exposed areas of the body, such as the face, ears, and neck. It can also present as a flat, flesh-colored, or brown scar-like lesion. BCC tends to grow slowly and rarely spreads to other parts of the body. However, if left untreated, it can grow into surrounding areas and cause damage.

Nonmelanoma skin cancers include

squamous and basal cell carcinoma, among others.

The skin consists of three layers

the epidermis (outer layer), the dermis (middle layer), and the hypodermis (innermost layer).

Skin Cancer Treatment

Chemical or thermal (liquid nitrogen) treatment may be used on localized nonmelanoma cancers caught early. Later cancer stages may require complete surgical excision and/or chemotherapy or radiation therapy, especially with metastasis to lymph nodes or organs.​ Melanoma cancer treatment involves the excision of the surrounding tissue, including the dermal layer, and may require skin grafting. Chemotherapy is often necessary. Newer treatments may include targeted genetic therapy and immunotherapy. ***Tanning is a sign of skin injury!​

Skin Cancer Diagnosis

Lesions are usually first noticed due to apparent skin irregularities. The ABCDE mnemonic is used to detect possible melanoma lesions. If a mole has an irregular shape, poorly defined border, uneven pigmentation, larger (usually than 6 millimeters), or is gradually or quickly changing, a referral and biopsy are required immediately. ​ Other warning signs:​ a change in an existing mole or spot on the skin​ a new growth or sore that does not heal​ a lesion with itching, bleeding, or crusting​ red patches or lumps that are tender or painful​ A skin/tissue biopsy is the definitive way to diagnose skin cancer. A sample of the lesion is cut, shaved, or punched out of the skin for a pathology review and diagnosis.

Pathophysiology of Skin Cancer

Skin cancer initiates in the epidermis and spreads depending on the type of cellular mutation. ​ Skin cancer is divided into two general categories. The body's immune system, if healthy and young, can stop the development of skin cancer. With age and factors that suppress the immune system, cancerous cells may evade immune detection by altering the expression of surface proteins or releasing substances that suppress immune responses. This immune evasion allows cancer cells to grow and spread.​ Chronic inflammation and oxidative stress can also play a role in skin cancer development. Prolonged skin inflammation or repeated skin injury can lead to increased production of free radicals and reactive oxygen species, causing DNA damage and contributing to cancer cell growth.

Skin Cancer Clinical Manifestations

Skin cancer signs vary depending on the type. Most cancers will have one or more of the following characteristics:​ a change in an existing mole or spot on the skin​ a new growth or sore that does not heal​ a lesion with itching, bleeding, or crusting​ red patches or lumps that are tender or painful​

skin

The skin is the largest organ in the body. To maintain its function, millions of skin cells are produced to build the layers of tissue necessary to protect the body from the surrounding environment.